| abstract |
A method for reducing the amount of a serine protease or a serine protease zymogen in a plasma-derived target protein composition, the method comprising the steps of: (a) performing a first stage of target protein enrichment to form a first composition enriched; (b) contacting the composition with finely divided silicon dioxide (SiO2) under conditions suitable to bind at least one serine protease or zymogen of serine protease; and (c) separating SiO2 from the composition to remove bound serine protease, in which the at least one serine protease or zymogen of serine protease is Factor XIa (FXIa), Factor XIIa (FXIIa), Factor XI (FXI), o Factor XII (FXII); wherein the first stage of target protein enrichment is a protein precipitation stage; in which the protein precipitation stage is an alcohol fractionation stage; and wherein the plasma-derived target protein is selected from an immunoglobulin (Ig), albumin, alpha-1-antitrypsin (A1PI), butyrylcholinesterase, a complement system protein, and an inter-alpha-trypsin inhibitor (Iα) |